Wheelchair users need their shoulders for mobility and all tasks of daily living. However, due to demands related to full-time wheelchair use, their shoulders are highly vulnerable to injury and are the most common injury location. Because they use their upper limbs every day, people in wheelchairs cannot rest their shoulders like able-bodied individuals when they are injured. For wheelchair athletes, who rely on their shoulders not only for daily life but also for vigorous training and practices, it’s especially important that we monitor shoulder health. At the University of Illinois— home to the official US Paralympic Training Center— our research focuses on shoulder strain during high-intensity interval training in world-class athletes. We use motion capture markers and EMG sensors, seen here on the subject’s arm, to determine how their arms are moving and which muscles are being used during handcycling. With this information, we can make computer models of the arm to calculate muscle strain and determine if some exercises during handcycling place the shoulder at more risk of injury than others. Ultimately, we hope to develop safe exercise practices that keep wheelchair users healthy and active without putting their shoulders at risk.